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Eating up to 3.5 ounces (100 grams) of chocolate daily is linked
with lowered risks of
heart disease and stroke, scientists reported today (June 15)
in the journal Heart. That amount of chocolate is equal to about
22 Hershey's Kisses, two Hershey bars or two bags of M&M's,
depending on how you want to divvy up this good news.

"There does not appear to be any evidence to say that chocolate
should be avoided in those who are concerned about
cardiovascular risk," the researchers concluded in their
paper. Their new study is based on a meta-analysis of eight
previously published studies involving a total of nearly 158,000
people.

One key finding was that people who ate chocolate regularly had
up to an 11 percent lower risk of developing cardiovascular
disease and a 23 percent lower risk of having a stoke, compared
with nonchocolate eaters. (Yes, remarkably, they exist.)

However, the analysis comes with more caveats than Almond Joy has
nuts. For example, exactly what it is about chocolate that might
impart health benefits is not clear. The scientists could
not determine a cause-and-effect relationship between the two,
and the observed benefits might be nothing more than a mirage, a
limitation of the study design. [ 5
Wacky Things That Are Good for Your Health ]

"There is, of course, a theoretical plausible explanation of why
eating chocolate in moderation may expose some [people] to
compounds — for example, flavonols — which are potentially good
for risk reduction through cholesterol- and
blood-pressure-lowering effects," said Dr. Phyo Myint, a senior
author of the study and a professor at the University of Aberdeen
School of Medicine and Dentistry in Scotland.

Myint cited numerous studies demonstrating that flavonols —
which are found in many plant-based foods, including cocoa
— can
lower blood pressure, improve blood flow to the brain, and
make blood platelets less sticky and less likely to clot and
cause a stroke.

But the majority of the participants in the eight studies in the
new analysis got their chocolate by eating milk chocolate, which
has considerably lower levels of flavonols than dark chocolate.
This left the researchers to speculate that milk components in
the chocolate — namely, calcium and fatty acids — may explain the
observed effect.

There are, however, several other plausible explanations for the
results that would suggest that eating
a lot of chocolate isn't necessarily healthy, the researchers
admitted. For example, the people in the study who ate the most
chocolate — more than 100 grams daily — were younger adults, who
tend not to have heart problems.

Similarly, the researchers said the finding might be due to
"reverse causation," meaning that the people with a higher risk
of cardiovascular disease avoid eating chocolate, while those who
are healthier eat more. The researchers also noted that consuming
too much candy and other high-calorie, sugary foods could lead to
dental cavities, obesity and diabetes.

Although the risk reduction linked with chocolate consumption was
statistically significant, the benefits are not particularly
striking compared with those of other dietary practices
associated with heart health. For example, outside the context of
chocolate, the risk of developing heart disease for these
participants given their age was 14.4 percent, on average, Myint
said. Therefore, reducing this risk by 11 percent would lower the
heart disease risk to 12.8 percent.

The study could not differentiate between the types of milk
chocolate consumed, and this could have health implications as
well. Myint's hometown of Aberdeen is where people devised the
now infamous deep-fried Mars bar, he said.

"The key is only to have moderate consumption [of chocolate] and
ensure one does not exceed the calorie intake recommended for
their height or weight," Myint told Live Science.